(Received: 2017-05-16, Revised: 2017-06-30 , Accepted: 2017-08-02)
Many current 10G optical systems need to be upgraded to higher data rates (for example 40G, 100G, etc…), in order to satisfy the increased demand for higher bandwidth. However, many system providers in the third world countries have limited budgets and could not just replace all equipment to upgrade their systems. Thus, it is important to investigate what equipment could still be used in the upgraded system. In other words; which equipment could be used for both 10G and higher data rate transmitters? The bandwidth of the passive modules is a crucial specification that enables optical communication systems. Therefore, the effect of multiplexer (MUX) and demultiplexer (DEMUX) bandwidth on the performance of hybrid 10G/40G optical communication systems is investigated in this work. Hybrid optical systems enable adding new channels with higher data rate on current 10G common equipment. Numerical simulations are conducted on eight consecutive dense wavelength division multiplexing (DWDM) channels selected on 100-GHz ITU-grid each carrying data rate of 10 Gbps or 40 Gbps. Different loading configurations of wavelengths with data rates are considered in this work. In addition, different MUX/DEMUX bandwidths of 40, 50, 60 and 70 GHz are used to investigate the performance of each selected hybrid system configuration. It is found that the optimal MUX/DEMUX bandwidth for all investigated hybrid configurations is 60 GHz. The hybrid system performance is evaluated for both return-to-zero (RZ) and non-return-to-zero (NRZ) pulse format. The maximum reach of a selected hybrid configuration is also numerically investigated using circulating loop configuration for both RZ and NRZ pulse formats.
  1. K. Fukuchi, T. Ono and Y. Yano, "10 Gbit/s-120 km Standard Fiber Transmission Employing a Novel Optical Phase-encoded Intensity Modulation for Signal Spectrum Compression," Optical Fiber Communication Conference (OFC’97), pp. 270-271, Feb. 1997.
  2. K. S. Cheng and J. Conradi, "Reduction of Pulse-to-pulse Interaction Using Alternative RZ Formats in 40-Gb/s Systems, " IEEE Photonics Technology Letters, vol. 14, no. 1, pp. 98-100, Jan. 2002.
  3. Y. Jiang, X. Tang, J. C. Cartledge, M. Poirier, M. Boudreau, K. Roberts and A. Atieh, "Electronic Dispersion Pre-compensation for 10.71 Gb/s NRZ-OOK Using InP and LiNbO3 Mach-Zehnder Modulators," Electron. Lett., vol. 47, pp. 865, 2011.
  4. J. Renaudier et al., "Performance Comparison of 40G and 100G Coherent PDM-QPSK for Upgrading Dispersion Managed Legacy Systems," National Fiber Optic Engineers Conference, CA, US, 2009.
  5. H. Bissessur, "40G over 10G Infrastructure-Dispersion Management Issues," Optical Fiber Communication Conference, Anaheim, California, United States, 2005.
  6. P. Winzer, "High-spectral-efficiency Optical Modulation Formats," Journal of Lightwave Technology, vol. 30, no. 24, pp. 3824-3835, 2012.
  7. L. N. Binh and T. L. Huynh, "Phase-modulated Hybrid 40Gb/s and 10Gb/s DPSK DWDM Long-haul Optical Transmission," Optical Fiber Communication and the National Fiber Optic Engineers Conference (OFC/NFOEC), pp. 1 – 11, 2007.
  8. M. Filer and S. Tibuleac, "DWDM Transmission at 10Gb/s and 40Gb/s Using 25GHz Grid and Flexible-bandwidth ROADM," Optical Fiber Communication Conference/National Fiber Optic Engineers Conference, Los Angeles, United States, 2011.
  9. O. Vassilieva, K. Croussore, I. Kim, T. Naito and T. Hoshida, "Suppression of XPM Penalty in Dispersion Managed Hybrid 10G/40G/100G DWDM Networks Using Group Delay Management," 35th European Conference on Optical Communication (ECOC-2009), Vienna, Austria, 2009.
  10. O. Bertran-Pardo, J. Renaudier, G. Charlet, H. Mardoyan, P. Tran, M. Salsi and S. Bigo, "Overlaying 10 Gb/s Legacy Optical Networks with 40 and 100 Gb/s Coherent Terminals," Journal of Lightwave Technology, vol. 30 no. 14, pp. 2367-2375, 2012.
  11. D. McGhan, C. Laperle, A. Savchenko, C. Li, G. Mak and M. O'Sullivan, "5120-km RZ-DPSK Transmission over G.652 Fiber at 10 Gb/s without Optical Dispersion Compensation," IEEE Photonics Technology Letters, vol. 18, no. 2, pp. 400-402, 2006.
  12. R. A. Griffin, A. Tipper and I. Betty, "Performance of MQW InP Mach-Zehnder Modulators for Advanced Modulation Formats," Optical Fiber Communication Conference (OTuL5), 2005.
  13. Z. Zhang, L. Chen, X. Bao and A. Atieh, "Partial Bit Delay Correlative Modulation Used to Improve the Dispersion Tolerance of an Optical Duobinary System," Optics Express, vol. 16, no. 15, pp. 11344-11353, June 2008.
  14. Y. Wang and L. Lyubomirsky, "Impact of DP-QPSK Pulse Shape in Non-linear 100 G Transmission," Journal of Lightwave Technology, vol. 28, no. 18, pp. 2750-2756, Aug. 2010.
  15. J. Toulouse, "Optical Non-linearties in Fibers: Review, Recent Examples and Applications," Journal of Lightwave Technology, vol. 23, no. 11, pp. 3625-3641, Nov. 2005.
  16. V. Kamalov, B. Koley, X. Zhao and C. Lam, "Field Verification of 40G DPSK Upgrade in a Legacy 10G Network," IEEE Conference on (OFC/NFOEC) Optical Fiber Communication (OFC), collocated National Fiber Optic Engineers Conference, San Diego, CA, USA, NTuC2, 21-25 March 2010.
  17. F. Yang, M. Mahic and L. Kazovsky, "Non-linear Crosstalk and Two Countermeasures in SCM-WDM Optical Communication Systems," Journal of Lightwave Technology, vol. 18, no. 4, pp. 512-520, Apr. 2000.
  18. A. Bononi, P. Serena and N. Rossi, "Non-linear Signal–Noise Interactions in Dispersion-managed Links with Various Modulation Formats," Optical Fiber Technology, vol. 16, no. 2, pp. 73-85, Mar. 2010.
  19. H. Zhang, A. Turukhin, O. Sinkin, W. Patterson, H. Batshon, Y. Sun, C. Davidson, M. Mazurczyk, G. Mohs, D. Foursa and A. Pillipetski, "Power-efficient 100 Gb/s Transmission over Transoceanic System," Journal of Lightwave Technology, vol. 34, no. 8, pp. 1859-1863, Nov. 2015.
  20. S. Bilal, K. Goroshko, H. Louchet, I. Koltchanov and A. Richter, "Non-linear Tolerant Modulation Format Enabled Tb/s Superchannel Transmission over 420 km of Unrepeated Raman Amplified Link," Optical Fiber Technology, vol. 36, pp 306-311, 2017.
  21. G. P. Agrawal, Non-linear Fiber Optics, 3rd Ed., Academic Press, Jan. 2001.